A026335 a(n) = T(2n,n-1), where T is the array in A026323.

1, 4, 21, 112, 615, 3432, 19382, 110432, 633555, 3654840, 21179389, 123195360, 718887585, 4206458700, 24671967210, 145008786304, 853852037038, 5035940194824, 29744992814381, 175921665090480, 1041700117634505, 6175002739467276

Offset

1,2

Links

Table of n, a(n) for n=1..22.

Crossrefs

Sequence in context: A010908 A136786 A301972 * A027909 A127111 A270787

Adjacent sequences: A026332 A026333 A026334 * A026336 A026337 A026338

Keyword

nonn

Author

Clark Kimberling

Status

approved